[PATCH 3/6] ARM: ux500: Enable support for RPMB and Reliable Write for eMMC

[Ulf Hansson]

On 27 May 2013 13:30, Linus Walleij <linus.walleij at linaro.org> wrote:
> On Thu, May 23, 2013 at 3:13 PM, Ulf Hansson <ulf.hansson at stericsson.com> wrote:
>
>> From: Ulf Hansson <ulf.hansson at linaro.org>
>>
>> By adding MMC_CAP_CMD23 for the eMMC devices, we can support RPMB
>> and Reliable Write. Additionally it will mean CMD12 will not be sent
>> to end a successful data transfer.
>>
>> Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
>
> Patch applied to ux500-core, thanks,
> but Houston, we have a problem:
>
> I wanted to enable this also for the device tree boot
> path. But currently there are no bindings to state in the
> DT boot that CMD23 is supported.

I should have realized that you were digging into this and should have
added such information in the commit msg/patch info. Sorry for that.
Anyway, I guess you see why I wanted to totally split the DT from
non-DT patches. :-)

>
> Could you create another patch that:
>
> - Add bindings to Documentation/devicetree/bindings/mmc/mmc.txt
>   for indicating that a host controller supports CMD23
> - Patch the ux500 DTS files to enable it.
> - Write a patch to mmci.c to augment
>   mmci_dt_populate_generic_pdata() to read the binding and
>   augment the caps from the device tree.
>
> There is also a complicated refactoring that need to happen any
> of these days:
>
> - Augment the MMC core and all drivers using DT boots to
>   parse any standard caps from the device tree insteaf of
>   putting code like mmci_dt_populate_generic_pdata() into
>   every driver.

Some parts of this is already done, the mmc common DT parse function
is called "mmc_of_parse". As of today it does not support CMD23 cap
though.
mmci should switch to use this function and drop the mmci specific dt function.

Kind regards
Ulf Hansson

>
> Yours,
> Linus Walleij